If you are small enough, and you are the only thing inside the blender, lie down on the ground in a way that the blades don’t touch you and just wait. No blender works forever and even if you wait long, you will survive.
If there are other things inside, unless you can climb them, it makes everything a lot harder to survive, as debris would hit you and probably throw you around, which would turn you just like any meat inside the blender, your best choice would be similar to the first, but you’d have to hold onto the pole that holds the blade in place in a fetal position, making sure the blade doesn’t hit your hips, but you are gonna have to hang on and pray it is fast, or you might drown when everything turns liquid.
If your hands are small enough, you can try to temper with the blade to make it useless. Trying to break the glass most probably would not work thanks to your reduced mass.
You can also try to put your back against the ground and push the tips of the blades up with your legs to bend them with the least resistance and try to create a void space on the sides of the blender glass, which would save you in both cases of empty and full blender, but you have to be strong enough for that.
In the end, the only choice is, try to find a way to survive, preferably turning the blender useless, try to find a way to get out. Either use your new size as a perk, when you find out how to survive being that tiny or try to acquire help to get to your original size.
If you do survive and get out, at least enjoy a good “giant” dessert before anything, you deserve it and giant food is one of the best perks of being really tiny